You could be running the incorrect octane or your local fuel is suspect or your tune is incorrect or a host of other reasons. Try loading a lower octane tune or tank-up with higher octane fuel and see what happens. Remember: when trying to use a higher octane fuel, you'll need to drive about 10-20 miles before the higher octane from the tank makes it to the engine immediately after filling the tank.

Thanks for the reply. I have been hoping I may have just gotten some bad gas and not something internal to the motor. I filled up this morning with 93 Octane so we'll see how things go over the next couple of days.

If it continues to knock with the new fuel, load a lower octane tune. It's not too uncommon for fuel in certain areas to be a bit "off" of their rated octane. It's posible you may just need to pull a degree or 2 of timing with the tuner. Altitude can play a role as well as other things. % ethanol doesn't always help, either.

This forum is owned and operated by Internet Brands, Inc., a Delaware
corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford
Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor
Company